The role of Th1/Th2 cell chemokine expression in hypertrophic scar

The aim of this study was to study the role of Th1/Th2 cell-associated chemokines in the formation of hypertrophic scars in rabbit ears. Twenty-six New Zealand white rabbits were used to establish the hypertrophic scar model of rabbit ear and the normal scar model of rabbit's back. Two rabbits were sacrificed on days 0 and 21, 28, 35, 42, 49, 56, and 63 after operation. The specimens were stained with haematoxylin-eosin (HE). Scar elevation index (SEI) was used to detect the expression of 10 chemokines related to Th1/Th2 cells in both scar formation expressions. Real-time polymerase chain reaction (PCR) results showed that two chemokines (CXCL10, CXCL12) were highly expressed during the formation of normal scar, and there was almost no expression during the formation of hypertrophic scar (*P < 0.05). The chemokines (CCL2, CCL3, CCL4, CCL5, CCL7, CCL13, CX3CL1) were almost non-expressed in the formation of normal scars but were expressed for a long time in the formation of hypertrophic scars. The four chemokines, CCL2, CCL4, CCL5, and CX3CL1, maintained a long-term high expression level during the formation of hypertrophic scars (P < 0.01). There were also three chemokines (CCL14, CCL19, CCL21) that were almost undetectable in normal scarring, but there was transiently low-level expression (P < 0.05) only during the peak proliferative phase in proliferative scarring. Th1/Th2 cell-associated chemokines are different in the type, quantity and expression, and maintenance time of rabbit ear hypertrophic scars.